P2848Electrical reconnections after pulmonary vein isolation with or without contact force-guided catheters: a comparison of the proficiency of atrial fibrillation ablation

Abstract Background Atrial fibrillation (AF) ablation is the most commonly performed catheter ablation (CA) procedure today. The 2015 ACC/AHA/HRS Advanced Training Statement reported that the success rate of AF ablation is higher in high-volume centers than in low-volume centers. We tested whether the procedure proficiency of each operator was associated with the outcome of AF ablation, and whether the ablation outcome depended on whether contact force (CF)-guided catheters were used or not, in a high-volume center. Methods We conducted a retrospective observational study including all AF patients who underwent radiofrequency CA with or without CF support since 2016 at our hospital. The patients who underwent CA at other hospitals or underwent a balloon or surgical ablation in the first session were excluded. Each ipsilateral pulmonary vein (PV) pair was divided into 8 segments. The reconnection numbers and sites of the PV segment were evaluated in the second session. Operators were divided into the experienced group (≥100 AF cases/year, at least every 3 years) and developing group (other than the experienced group), respectively. Results Among 728 patients who underwent an initial AF ablation and were followed for 510±306 days, 131 (90 males, 65±10 years) received a second ablation procedure and were analyzed. A total of 260 and 264 PV isolations (PVI) were performed by the experienced and developing group operators in the initial ablation, respectively. Compared to the experienced group, the developing group had a longer procedure time for the PVI (35±15 vs. 28±10 min, p<0.001), higher frequency of reconnections of the PVs (73% vs. 59%, p=0.01) and higher number of reconnection gaps (2.1±2.0 vs. 1.5±2.0, p=0.02), respectively. There were no significantly differences in the number of gaps between the catheters with and without CF (1.6±2.0 vs. 1.4±2.0, p=0.65) in the experienced group, however, in the developing group a smaller total number of gaps (1.5±1.6 vs. 2.4±2.1, p=0.006) and less frequency reconnection gaps of the posterosuperior segment of the right PV (10% vs. 45%, p=0.005) were seen with catheters with CF than without. There was no significant difference in the procedure time for the PVI between catheters with and without CF. Conclusions The operator proficiency may predict the outcome after AF ablation even in high-volume centers. It is preferable to perform PVI with a CF-sensing catheter for operators without adequate proficiency. Acknowledgement/Funding JSPS KAKENHI Grant Number JP18K15865